Table 1. Characteristics of included studies.

No.	Author	year	Experimental group					Control group					Follow up time(year)
			Number (n)	Age (Mean±SD)	Male (n)	Type of stone	Method	Number (n)	Age (Mean±SD)	Male (n)	Stone type	Method
1	Dussol	2008	115	44±12	60	Calcium oxalate	55 patients receive low doses protein (<15% of total energy) and 65 patients receive high doses fiber(>25g) per day	63	45±11	38	Calcium oxalate	Normal diet	4
2	Sarica	2006	12	-	-	Calcium oxalate	Enforced fluid intake (achieve to more than 2.5 liters of urine per day)	9	-	-	Calcium oxalate	Nomal diet	3
3	Borghi	2002	60	44.8±9.2	60	Calcium oxalate/ Calcium phosphate	Normal Ca with reduced protein 52g/d and salt 50 mmol/d	60	45.4±10.9	60	Calcium oxalate	Traditional low Ca diet	5
4	Kocvara	1999	113	18–72	59	Calcium stone	Special dietary regimens with low proteins, purine, oxalate and high fiber.	94	18–72	37	Calcium stone	Normal diet	3
5	Hiatt	1996	50	43.1±1.5	36	Calcium oxalate	56–64 g/d protein, 75 mg/d purine, fiber supplement and 6–8 glasses of water	49	42.9 ± 1.4	42	Calcium oxalate	Fluid intake	4.5
6	Borghi	1996	99	42.2±11.6	70	Calcium oxalate	Enforced fluid intake (achieve to more than 2 liters of urine per day)	100	40.4± 13.2	60	Calcium stone	Normal diet	5